The jilted ex-fiancée of top chef Todd English was caught swiping more than $1,000 of cosmetics from a Midtown Sephora — just two weeks after her confessed shoplifting spree at nearby Ralph Lauren, sources told The Post.

Erica Wang, 36, suffered an apparent meltdown Monday when a security guard stopped her from leaving the Lexington Avenue shop with the stolen designer makeup and perfume, which she allegedly had stuffed into a Louis Vuitton bag.

“She said she was going to run out into the street, throw herself into a car and kill herself,” one employee of the trendy shop said.

“She was crying. She was on the floor screaming, on her knees, screaming that they were going to send her to a mental institution. She begged not to get arrested and offered to give the stuff back,” a witness added.

Wang even name-dropped English, telling cops she was once engaged to the celeb chef — though she didn’t mention how he famously dumped her on their planned wedding day.

Workers spotted Wang filching the designer cosmetics — including Dior, Yves St. Laurent and Urban Decay — as soon as she walked in the door.

They eyeballed her for a full hour as she walked around the shop grabbing more and more items — 41 in all, valued at $1,131 — and finally stopped her as she tried to leave without paying.

“She stole from almost every brand in the store. She was obvious about it,” a worker said. “When she walked out of the door, she said, ‘I’ll pay double for everything! Please!’ ” a worker said.

“It took [cops] 15 minutes to get down the stairs. She knelt on the floor. She said, ‘I have money.’ She pleaded with her hands clasped, ‘I’m the ex-fiancée of Todd English!’ ”

Wang was released without bail after being arraigned in Manhattan Criminal Court on one count of grand larceny and one count of possession of stolen property.

“My client does have emotional-slash-psychological problems. She does feel she has a problem,” Caroline Ng, her Legal Aid lawyer, told the judge.

Wang, stylishly dressed in a sleeveless navy-blue top and white pants, refused to comment after court.

The Post first reported that Wang was arrested July 26 at Ralph Lauren’s flagship store on Madison Avenue. She admitted to stealing about $52,000 worth of merchandise.

She later confessed to having swiped another $46,000 worth of items while working there.

She was also busted on Feb. 23, 2004, for boosting merchandise from Bergdorf’s luxury emporium on Fifth Avenue.

English — the hunky chef behind The Plaza Hotel Food Hall and other hot eateries — called Wang hours before their October 2009 wedding and said, “I can’t marry you today.”